Thermal-controlled shutter.



E. CAHILL.

THERMAL CONTROLLED SHUTTER. armcmon nuso MAR. us. me.

Patented A r. 3,1917.

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lF; Tfitldlid PA 5 in i EDWARD careful, or new YORK, n. Y.

THERMAL-CONTROLLED SHUTTER.

Application filed March 16, 1916.

This invention relates to thermal-coir trolled shutters or doors for automatically closing passage ways or windows in case of fire in order to prevent an extensive conflagration.

It is the aim of this invention to provide a closure of this kind which will be more reliable in operation but which will not be apt to be released accidentally, such accidental release in .prior devices having caused the stripping of gears and sometimes even the loss of life. Another object is to provide an improved form of ratchet wheel and pawl mechanism for controlling the shutter and which may be used interchangeably at either side of the door or window opening. A further object is to provide means for securing the pawl in locked position to permit the supporting chain to be loosened, when repairs or adjustments are to be made, without danger of the shutter falling.

The invention will be first hereinafter described in connection with the accompanying drawings, which constitute a part of this specification, and then more specifically defined in the claim at the end of the description.

In the accompanying drawings, wherein similar reference characters are used to designate corresponding parts throughout the several views:

Figure 1 is a broken front elevation of a shutter constructed substantially in accordance with the present invention, said shutter being illustrated in its closed .or lowered position.

Fig. 2 is a longitudinal vertical section through the shutter and the means for supporting the same.

Fig. 3 is a broken horizontal section through the hollow shaft on which the shutter is rolled.

Fig. 1 is an enlarged transverse section through the left hand end portion of the shaft, showing the locking pawl in active position, as when the shutter is held in its raised position and the fusible link and Specification of Letters Patent.

Patented Apr. 3, 1917..

Serial No. 84,576.

chains connected thereto are fastened in the position indicated'in dotted lines in Fig; 1. Fig. 5 is a detailed view of the special pawl ans} ratchet wheel drawn to a larger scale, Fig. 6 is a detailed'view of the train of gears at the right hand end of the shaft for raising the shutter.

The shutter 1 is of the rolling type and is adapted to move vertically in guiding grooves 2 at the sides of the passage way 3. At the top of the passageway the shutter is attached to collars a fast on a hollow shaft 5 which is inclosed in a casing 6. The shaft 5 is hollow and has its left hand end j ournaled around a hollow lug 7 which is part of a supporting bracket 8. Journaledwithin the lug 7 and preferably running within ball-bearings 9, is a notched wheel 10, the shank 11 of which extends entirely through the lug 7. A coiled spring 12 is housed within the left hand section of the shaft 5 and has one of its ends attached to the inner end of the shank 11 of the notched wheel 10, the other end of the spring being fastened to a pin 13 fitted transversely to the shaft. The wheel 10 may have a bearing pin 110 journaled in the bracket 26, Fig. 3.

The right hand end of the shaft 5 is fastened to a collar 14 journaled around a stud 15 rigidly fastened to right hand end plate 16 of the casing 6. The stud 15 extends inward beyond the collar 14 and is attached to one end of a coiled spring 17 which is housed in the right hand end section of the shaft has a gear wheel 20 rigidly mounted thereon beyond the end of the shaft 5. A train of gears 21 communicate rotary motion from the collar 14, and shaft 5 which is rigidly fastened to the same, to an auxiliary shaft 22 also carrying a sprocket wheel 23. This sprocket wheel 23 is fitted with a sprocket chain 25 which may extend down within reach of the operator and be used for raising the shutter.

Pivotally mounted on the left hand end wall 26 of the casing 6 is a pawl 27 having two teeth or projections 28 and 29 at opposite ends thereof. The pawl is pivoted at 30 near the end bearing the tooth 28, which is the lower end of the pawl when the same is in locking position,'as shown in Figs. 4 and 5. WVhen in this position, the teeth 28 and 29 extend into adjacent notches 31 and 31 in the wheel 10 and the pawl is arranged in an inclined position so that when re leased it will automatically swing down to the unlocked position illustrated in Fig. 2. The pawl is arranged in locking position, Figs. 4 and 5, when the shutter has been rolled up on the shaft 5, and said pawl is held in this position by achain or other flexible connection 32 which is passed over bearing pulleys 33 above the shaft and within the casing 6, and down through the bottom portion of the casing and along the front thereof where it is secured by a fusible link 34 Fig. 1. The fusible link may be fastened directly to the bottom of the casing, or another section of chain 35 may be connected to said link and have its other end made fast to the right hand end of the easing, see Fig. 1.

When the shutter is installed, the tension' of the spring 17 is, according to the weight of the shutter, made such as to prevent its violent descent when the shutter is liberated from the tension of the spring 12. The tension of the spring 17 also permits the shutter to be evenly rolled up by means of the sprocket chain 25 and train of gears 21. When the pawl 27 is engaged with the notched wheel 10 for supportingthe shutter in raised or rolled up position, the spring 12 is tensioned to retain or counterbalance the shutter. Now, whenthe pawl is released from the notched wheel 10, which will occur whenever the temperature rises sufliciently to fuse the link 34, as in case of fire, the

tension of the spring 12 will be relieved andv the counterbalance being thus destroyed, the shutter will fall from its own weight. As the shutter falls, the tension on the spring 17 is increased so as to cushion the descent of the shutter.

Referring again to Fig. 4, the tooth 29 at the free end of the pawl 27 serves to lock the tooth wheel 10 by engaging one ofthe notches 31 in its periphery. The other tooth 28 extends into one of the notches 31 in the wheel 10 and when the pawl is released is struck by the wall of said notch, thereby throwing the pawl outward with the tooth 29 entirely free from the notch which it hadengaged. Both of the teeth 28 and 29 are pitched so as to engage only one of the walls of each notch.

7 The notched or ratchet wheel 10 is made half of the periphery of the wheel has three pairs of notches 31 and 31 inclined and arranged in proper relative position to be engaged by the teeth 28 and 29 of the pawl 27 when said pawl is mounted as indicated. The right hand half of the periphery of the wheel has three pairs of notches 31 and 31 oppositely inclined and arranged in opposite relative position as compared with the notches 31 and 31 so as to permit said wheel to also be used with a reversed pawl, as indicated in dotted lines in Fig. 5, when the shaft is reversed as may be desirable in some instances in order to place the shutter raising sprocket chain at the opposite side of the door or window opening from that illustrated in the accompanying drawings.

While three pairs of notches are shown by way of illustration on each side of the wheel 10, it will be understood that the number of said notches may be increased at will so as to provide a wider range of adjustments in each position of the pawl. Of course, in one position of the pawl, such as that shown in solid lines in Fig. 5, the range of adjustment will include only the notches 31 and 31 on one half the periphery of the wheel, while in the other position of the pawl, as suggested in dotted lines in Fig. 5, the range of adjustment throughout the other half of the periphery of the wheel having the notches 31 and 31, but the number of the notches 31, 31 31 and 31 may be increased as much as desired v according to the relative sizes of the wheel outside, as shown, it is more accessible.

Said bolt is adapted to be screwed in so as to engage a recess or passage 37 in the pawl for holding the latter in active position with its teeth extending into the notches in the wheel 10. When the bolt is turned in a reverse direction its inner end may be retracted from the passage 37 in the pawl, leaving the latter free to swing down and away from the wheel 10 when the chain 32 is released.

It will thus be seen that I have provided a thermal controlled shutter or door with a loose shaft which facilitates my desired object, for upon release of spring the shaft 5, which is journaled around the hollow lug 7, is driven reverse to wheel 10 and positively releases the pawl. It will also be noticed that gravity, without the aid of the spring, will also release the pawl when link is fused.

While I have shown some of the train of gears 21 arranged outside the end plate or bracket 16, in Figs. 1 and 6, it will be understood that all of these gears may be inclosed in the casing 6, or if desired parts shown inclosed may be exposed without departing from my invention. The sprocket chain 25 may also be arranged inside of the casing as well as outside thereof.

It will be understood that the ratchet wheel 10 and pawl 27 may be arranged at either the right hand or left hand end of the casing and either inside or outside the end brackets of said casing, thus providing Copies of'this patent may be obtained for four dilferent applications, two at the right hand end and two at the left hand end.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

Thermal controlled locking means for shutters, including a reversible ratchet wheel having in one portion of its periphery a series of notches inclined in one direction, and in another portion of its periphery a series of notches inclined in the opposite direction, and a pawl adapted in one position to engage one series of notches and when reversed to engage the other series of notches in the wheel.

In testimony whereof I have signed my name to this specification.

EDWARD CAHILL.

five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

